Why is the universe expanding at an ever-increasing rate? This is one of the most exciting yet unresolved questions in modern ...

Planets that orbit white dwarf stars should be too hot to host alien life, theories suggest. But a new study accounting for ...

The story begins with the black hole information paradox. According to relativity, anything that falls into a black hole is ...

Gravitational waves are energy-carrying waves produced by the acceleration or disturbance of massive objects. These waves, ...

Astronomers have captured the first radio image of two supermassive black holes orbiting each other within the quasar OJ287, ...

For two decades, scientists believed the cosmological constant, known as λ (lambda), was positive. That meant the Universe ...

Evolving dark matter may explain cosmic acceleration. Observations support a mixed model. For years, a stubborn puzzle has sat at the center of the standard cosmological model. The evidence clearly ...

Time is not absolute, and Einstein argued that different observers experience the present differently depending on relativity ...

A new look at radio maps of the sky shows a pronounced tilt, called a dipole, that astronomers are still unable to explain ...

Astronomers studying the supermassive black hole M87*, a behemoth six and a half billion times the mass of the Sun, have uncovered a new way these cosmic monsters unleash their power.